Tweeking the boat?

[Sandman_28054]

Now I presume we are all familiar with the "Delta Renown" trick.

In the Patrols_0 file, there is listed

SubType=1
SubVersion=0
SubName=U-51

I am currently in a Mark 7 (VII). (21/3/40 is the current date)

I see that during this time there is also a Mark 9B (IXB) available.

Is there a way to change this? Can this be tweeked?

Or should I just bide my time?

Thanks in advance.