The open question is, again, what will be the percentage of such cases.
I don't doubt that reinfection will be rare, at least over the span of a few months, but to my mind that would seem unproven given how hard we're (generally) working to keep people from being infected in the first place.
'Quite high' could mean anything, but if you're implying 'higher than' then that isn't supported by the statistics I've seen in a dozen countries.
No. From the current papers, we just know that the reinfection where people have had their virus sequenced in both first and second infection is very rare.
The problem is technological. Up to now there are around 50 million confirmed cases in the world but probably less than 100 thousand sequencings performed, and only a few sequencings by those who had strong enough symptoms twice and had the chance to have sequencing twice.
Without sequencing one just can’t prove that some case is an actual reinfection. All other cases are just “possible” (i.e. unprovable) reinfections and nobody can claim anything worthy of a scientific paper about them.