In 1866 the mail contract was amended for the Mail Packet to remain at Aden only sufficient time to take on coal, and that this must not exceed 48 hours.

In January 1868 the Indian Government added an additional mail steamer on the Aden-Bombay leg of the mail route from England to India; the steamer would leave Aden for Bombay on the arrival of each English Mail Packet from Suez for Calcutta. This meant that there would be about eight mails to and from Bombay each month. Including French mail steamers, mails to and from Europe averaged about six a month. About 45% of mails arrived at Aden at night, all being processed on arrival.

Due to the increasing problem of the silting up of the Inner Harbour, in 1870 the Mail Packet sometimes had to leave Aden early (i.e. spending less time there than that stipulated in the contract) in order to catch the tide. Also in that year the Franco-Prussian war caused some worries and uncertainties to the UK-India Mail Packet service. At the time there were three different routes available: via Marseilles, via Brindisi or via Southampton, there being a different rate for each route. The all-sea route, taking several days longer than mail being sent across Europe by rail, was the cheapest. The Aden Postmaster issued a Postal Notice in early November 1870 stating that owing to the war the Marseilles route for mails for England was about to be discontinued until further notice but that letters could still be sent either via Brindisi or Southampton. The inference from this Notice is that the Brindisi route was already an alternative to Marseilles and that it was not introduced when that route was temporarily shut down. But once operating from Brindisi the P & O Packets used that port from then on.

As for Mauritius the possibility of interruption would have a much greater effect as the monthly mail service to England was via Marseilles. Hence earlier that year the Colonial Secretary’s office in Mauritius had sent that colony’s mails in sacks addressed to the Aden Postmaster, with a covering note asking him to use his discretion as to whether to send the sacks on via Marseilles or Southampton. Another letter requested that in the event that the Messageries Imperiales steamship service was interrupted the outward mails should be sent by the first available steamer to Galle in Ceylon, from where they would be brought back to Mauritius.

In early November 1872 Mr Waller, the Aden Postmaster, issued a Postal Notice that there would soon be a monthly packet between Aden and Table Bay (Cape of Good Hope). The packets would call at Zanzibar, Mozambique and Natal in both directions. The service would commence on 5th December from Aden, thus allowing the packet to take mail from the mail steamer that had left Brindisi on 22nd November and also the mail steamer that had left Southampton on 14th November. (This gives one a good idea of the time saved by sending letters via Brindisi.) The packet would commence the return journey from The Cape on 30th December. The departure date from Aden was changed later to 6th December, with a packet to leave Aden every fourth Friday thereafter. This service was referred to as the ‘Zanzibar Mail’. In 1883 the contract for the Zanzibar and Lindi Mails specified that the steamer used for this service must be not less than 700 tons and have a speed of not less than 7.5 knots, except that during the monsoon an additional 48 hours was allowed for the journey. In addition the contractor would be obliged to call at two other ports between Aden and Zanzibar. The volume of mail to and from Zanzibar (that is to addresses in Zanzibar, bearing in mind the trading between the two locations) was quite high – about 210,000 letters a year to Zanzibar and about 170,000 a year in the other direction.

The Nord Deutscher Lloyd steamers began the following packet services in 1886: ‘China Line’ from Bremen via Naples, Suez, Port Said and Aden to Colombo, Singapore and Hong Kong; ‘Australia Line’ from Bremen via Aden to Colombo, Melbourne, Sydney and Adelaide; and ‘East Africa Line’ from Hamburg via Aden to Lamu, Mombasa, Tanga, Zanzibar, Dar-es-Salaam, Mozambique, Delagoa Bay, Durban and East London. To save time the China Line mail was sent overland from Hamburg via Munich and Kufstein to Naples.

A Postal Notice issued early in December 1887 warned that due to the terms of the new P & O contract which was to come into force on 1 February 1888, the stay of the Outward and Homeward Mail Packets in Aden would be reduced from six to three hours. P & O subsequently changed the shipping programme and for some sailings decided on a transhipment of mails and passengers at Aden instead of at Suez; this took place every fortnight and the time of stay of mail boats was, in consequence, often extended beyond the three hours.

During 1888 Messageries Maritimes modified their Australian Line programme and opened up a new East Africa Line from Port Said to Obock, Aden, Zanzibar and Reunion. As a result there was a bi-monthly mail for and from Mauritius and Reunion and steamers also called at Zanzibar. It was therefore opportune to send mails for Zanzibar by Messageries Maritimes steamers. In the same year the Director General gave permission for correspondence from Aden for the United Kingdom to be sent by Messageries Maritimes packets is this was opportune.

In 1888-89 the contract with the B.I.S.N. Co for the packet to Zanzibar was renewed but the new one stipulated a minimum speed of 11 knots for packets, an increase of two knots from the previous contract. [The contract signed in 1883 had stipulated seven and a half knots - see above.] Also in 1888-89 the Hodeida mail service by a local coasting steamer became regularly established. This was run by Cowasjee Dinshaw.

During 1891 additional postal links with Zanzibar became available using Portuguese and additional German steamers on the East Africa route.

During 1898-99 a total of 848 mails were received and 817 despatched, an increase of 12 and 62 respectively over 1897-98. In addition no less than 2,119 Naval mail bags passed through the Post office, 315 of which were for local delivery; 1,196 were for the East Indies Squadron and 608 for the Cape of Good Hope and West African Squadrons. During the year mails were twice despatched from Aden to Mukalla and Shehr, but no mails were received.

Mail delivery aboard HMS Cruiser in Aden. circa 1890

In 1899-1900 the packet programme was as follows: The P & O outward packet from Brindisi arrived on a Monday and the homeward packet from Bombay on a Thursday, except in the monsoon season when it arrived on Fridays. The French packet to and from China via Bombay called once monthly to no set date; the French packet to Mauritius and Madagascar called monthly, on the 6th or 7th in alternate months, returning on the 12th or 13th of the month. German packets to and from China and Australia called monthly. In addition an Italian packet called every Wednesday with mail from and for Red Sea ports. In that year 942 Sea Mails were received and 891 despatched. A total of 22,563 bags were handled, 12,936 of which were received and 9,627 despatched. Of those received, 7,608 were for Aden District and 5,328 for onward transmission by various shipping lines. A further 1,738 mail bags were received for HM Ships.

A Supplementary Mail Contract was signed with P & O for period 31 January 1905 to 31 January 1908 for the Brindisi-Bombay Mail Steamer to cover the journey within 278 hours, which only allowed a 3 hour stop at Aden. [The three hour maximum stopover of 1888 had obviously extended in the meantime.] The Outward Mail would probably arrive on a Sunday evening and the Homeward Mail on a Wednesday evening, except during the southwest monsoon when the transit time from Bombay to Brindisi would be extended by 36 hours. By 1905-06 the total number of bags handled had risen to nearly 29,500.