I'd recommend going once before sharpening just to see how it goes.I think I need to get my blades sharpened first. Before I stopped with ankle problems I remember thinking they needed it. Though it might be a double whammy - skating for the first time in over a year and on freshly sharpened blades...i'll have to think about it.
If you feel that dull edges are holding you back more than the time off, then get them sharpened before your next time on the ice.
If you feel you need to acclimate your body to skating again before adding too-sharp blades for the next few sessions, then wait until you're acclimated.
Either way, if you think you will start lessons again while still readjusting to the ice or first adjusting to a new sharpening, make sure your coach is prepared to focus during the first lesson on the acclimation rather than expecting to pick up right where you left off.