If you can, don’t let it actually expire - revalidation is easier (from a paperwork point of view) than renewal.
Revalidation/renewal tend to be “easier” or perhaps less stressful as you’ve already experienced the test conditions so have a better understanding of what’s to come.
With regards to staying current, I would recommend flying as much as you can afford to (little and often) even if that’s in a simulator. Keep up your planning skills by planning trips you’d like to do if money were no object. There will be others (perhaps from your group) in the same position so perhaps “buddy up” some flights to stretch the budget and challenge yourself.
Historically the aviation industry is very cyclical so keep plugging away and working to achieve that first commercial job but bear in mind it might be a few years away.