Visa Curtailed, Out Of Time Application with New Sponsor

[TheSpread]

My last visa was curtailed and I was given a few months to get a new sponsor. The organisation who are working on processing a new ceritificate of sponsorship for a Tier 2 Visa are not aware of how time sensitive my case is. I was wondering if, in the case of a visa that was curtailed, I still get a 28 day leeway to make an application after the date on the letter of curtailment?

Also, I reach my 10 year long residence status soon so I was wondering whether me overstaying by a few days within the 28 day leeway would affect an application for indefinite leave to remain.

Many thanks!!