The return flight organized by the European Community and initially scheduled for Tuesday, April 21 from Nairobi to Frankfurt with Ethiopian Airways has been moved to Thursday, April 23 to facilitate the possibility to organize in time also by applicants from the Kenyan coast. The price of the ticket has also been decided, which is 1443 dollars (about € 1330) to which a Frankfurt-Milan or Rome ticket will have to be added.
Here is the communiqué of the Italian Embassy on the matter:

Attention: Flight postponed until next Thursday, April 23rd. Price 1443 USD.

Follow the link to reservations (not yet open). Please note that reservations for the flight must be made directly on the airline's website (https://www.ethiopianairlines.com).

Any special requirements may be communicated directly to the airline in the manner indicated on the Ethiopian Airlines website.

Connections from Frankfurt to Italy:
From Frankfurt there are daily flights with Alitalia (to Rome) and Lufthansa (to Milan and Rome). The German authorities require passengers travelling in transit through Italy to be in possession of an appropriate ticket, which must therefore be purchased prior to arrival in Frankfurt. For further information, please consult directly the website of the Consulate General of Italy in Frankfurt.

With regard to travel on Kenyan territory to Nairobi JKIA airport (according to the information received, there is currently no stopover in Mombasa for this flight), please note that this can only be done by land, bus or taxi, as, as part of the measures taken by the Kenyan authorities to deal with the coronavirus emergency, all internal air connections have been suspended.

It is recommended that you contact this Embassy immediately after purchasing your ticket, in order to facilitate obtaining the necessary authorization to travel between counties that will have to take place overland.

In case of group travel, particularly from the coast, this may be coordinated by the European Union Delegation or Embassy.

Due to a central technical problem, the information contained on the website of this Embassy is not up to date at the moment.
Further updates will continue to be published on the social pages.

Please note that you can contact the Embassy on the following emergency numbers:
+254 722 514 327 or +254 110 093 926.