Mark.
I guess the filling time shall vary depending on how you fill them, by natural flooding the filling pressure surfaced varies between appr. 2 mWC. and 0, capacity of one reg. tank 7,6 m3. piping appr. 100 mm., if you fill with the main bilge and ballastpump you might have a filling capacity of 1,3m3/min against 15 m WC however restricted to a pipe diam of appr 100mm., the reserve fuel and reg. tanks 1 have a capacity each of 4.7 m3 and have of course a shorter filling time. Otherwise, submerged the filling pressure by natural flooding varies with the depth. I never logged the time , but I guess with the above input you are able to estimate the time, remember the inboard venting pipe which might influence the head due to resistance in pipe and muffler.
Only the main ballasttanks 1, 2 and 4 port and stb.,3 and 5 are possible to blow by exhaust.
Tore