Re: How about some grace time after expiry?
There effectively already is this embargo.
After your expiry date, they tend to wait 30 days before dropping your glue records. Then 60 days after that your registration is deleted. During that time you can renew, but no-one else can buy the domain - however, in the final 60 days you may have to pay an additional fee.
So that's 90 days after domain expiry, and after 60 days of outage that the opportunity arises for someone else to buy your domain.
And you get multiple, regular emails telling you that your domain is coming up for expiry, has expired and is in the grace period, is now in the redemption period, will be released, gone.
The timings are different (tighter) for .com and other TLDs.
I recently had all that with a domain I _wanted_ to let lapse. The repeated emails are kind of frustrating in that scenario, because you can't really miss them
My guess is that they hit the redemption period, didn't want to pay an additional £60 fee, so figured they'd wait for it to hit the market and then renew for 15.99 and lost that gamble.