1.
gap period between harvests
The period between the end of one harvest and the beginning of the next, when supplies are low.
2.
off-season, slow period, transition period
A period of reduced activity or supply between two busy seasons or product cycles.
端境期 refers to a gap or transition period.
Etymology
From 端 (edge) + 境 (boundary) + 期 (period), literally 'boundary-edge period'.
Original meaning
Originally referred specifically to the agricultural period between rice harvests when old rice was depleted and new rice wasn't yet available.
Modern usage
Now broadly used for any off-season or transition period in business, tourism, retail, etc.
Common patterns
Related Words
Compare:
季節の変わり目 (change of seasons)