Yes, you can have a fleet ret to bay as on Nile. Could have done this a day or 2 ago but did not notice in Yahoo mail mess. The 1 player game I'm in is nearly as gunboat as this so will be done with my part soon which will help. Gb02  the most advanced as is. GB05 has been a chore from start (W04 current).  http://www.diplomaticcorp.com/game_page.php?game_id=dc470
 
Rome:
F Neapolis Supports F Sicilia (*Dislodged*) RET TYR (ION)
F Sicilia Supports F Neapolis
Carthage:
A Apulia - Neapolis
F Ausonian Sea Supports A Apulia - Neapolis
F Berber Sea Convoys A Mauretania - Massilia
A Etruria Supports A Mauretania - Massilia
A Leptis Supports A Numidia (*Cut*)
F Ligurian Sea Convoys A Mauretania - Massilia
A Mauretania - Massilia
A Numidia Supports A Leptis
F Punic Sea - Thapsus
F Roma Supports A Apulia - Neapolis
F Sardinia - Punic Sea
Persia:
A Arabia - Jerusalem
A Chersonesus Supports A Sarmatia (*Ordered to Move*)
F Egyptian Sea Supports F Memphis - Alexandria (*Cut*)
A Jerusalem - Sinai
F Memphis - Alexandria (*Dislodged*) RET BAY
A Petra Supports A Jerusalem - Sinai
A Sinope Supports A Galatia (*Ordered to Move*)
F Syrian Sea - Gulf of Pelusium (*Fails*)
Greece:
F Adriatic Sea Supports A Ravenna
A Byzantium Hold
A Galatia - Miletus
F Gulf of Syrtis - Leptis (*Fails*)
F Gulf of Tacape Supports F Gulf of Syrtis - Leptis
F Libyan Sea - Crete
A Ravenna Hold
A Rhaetia - Massilia (*Fails*)
A Sarmatia - Vindobona
Egypt:
F Alexandria Supports A Thebes - Memphis
A Cyrene Supports A Thebes - Memphis
F Gulf of Pelusium - Egyptian Sea (*Fails*)
A Thebes - Memphis
 
Adjustments:
Rome:      Supp  1 Unit  2 Remove  1
Carthage:  Supp 11 Unit 11 Build  0
Persia:    Supp  9 Unit  8 Build  1
Greece:    Supp 10 Unit  9 Build  1
Egypt:     Supp  3 Unit  4 Remove  1