No.
If you fly at 2100ft, and the upper limit is 2100ft, you will be infringing the restricted area.
If you fly at 2101ft you will not.
Bear in mind that, if you overfly a danger area at 1ft above the notified restricted altitude there's a very good cahnce no one will notice and you'll be safe from whatever is going on there because whoever runs the area has decided that at that level you'll never come into conflict with whatever it is that's going on below.
If you overfly a restricted area 1ft above the notified level, it will be difficult for whoever has established the area exactly what level you are at, you will be considered a threat, and counter measures are highly likely to be taken.
It's your choice
