Is two weeks enough to get ready for 3' jumpers?

Is two weeks long enough to get a horse ready for 3' jumpers? He is being ridden outside, and occasionally lunged and jumped to 2'6. He seems to keep in good condition, and retain muscle. The jumps usually need to be at least 2'6 for him to actually jump it. He has done to 2'9 jumpers, and schooled to 3'9. He is 7yrs old.

Is your horse coming up from rest or is he currently in work?
   
Remember the most simple fittening programmes (from rest) take 8 weeks at the minimum to get a horse fit.
   
Speak to a BHS Qualified instructor about fittening your horse up for jumping competitions.