GWX Question, 7th Flotilla

[U-48Kriegsmarine]

I just started a new career in 1939 in the 7th flotilla (thanks to alternative flotilla mod from GWX) and while out on the first patrol in the bay of knoingsberg, i get a message adressed from the GWX team telling me to return to port and transfer to either the 1st or 2ne flotilla. is this absolutly nessicary, and if so when can I transfer back to the 7th?

Thanks,

Dave