Short on Time

I am solo masters swimmer who enters about four meets a year. This past year I transferred to a new school (I am a school administrator) and the work load was insane. Long story short...my swimming suffered. Yes, I know, make swimming a priority and blah-blah...well, easier said than done, and I can't undo the past now anyway. I actually had a spell of six weeks where I didn't swim at all. Now, I have been back to the pool...in the last four weeks, I've been logging 3-4 times in the pool per week, which is what I usually do...5 is a good week. It is easy to get out of shape...my first day back after the layoff I felt dead after 20 laps, but it also seems to come back just as fast...a few days back and I didn't feel like I had lost that much. My question...I have a meet on June 20th (non-sanctioned). Last year I did a personal (masters) best of 30.54 in 50 meter short course free (I'm 56 y.o.), which I subsequently lowered to 30.37 a few months later. What is my best strategy for getting in race shape quickly...for basically 2 sprints...50 meter free and 50 meter ***? I don't mind working hard, but I am also wondering if there is a danger of burning myself out if I go too hard suddenly in too short a period of time. Is it possible to "play catchup" or should I just revert back to doing the same workouts I did last year at this time?