Exactly so easy to work on, if they had to remove the AT that would only be an extra half hour or so....but.... is it causing problems, got a leak or whatever? because if it isn't can't see the point of a "service".
Might as well wait until it has to be stripped for reblueing or replacement, cost me £45 for a new carbine cylinder earlier this year just before Debens took over so probably dearer now.