Boarding, Unable to use Deckguns...

[Norfolk nChance]

 

Quick question,

Was boarding an LGV and I noticed my deck guns remained greyed out the entire action of boarding. Does anyone know why?

I haven't included details to see what the mechanic is? We did a good few rounds more than the 3x it says to reload. With the boarding action my gun crew was under crewed and switch off (greyed) out 

[qw569😳]

The command is unavailable if deck difference between the ships is greater than 1