What happens to US military demo teams following unexpected pilot turnover? Following up on recent events involving the Blue Angels and the Thunderbirds, what is the typical procedure for these teams following a unexpected turnover of a pilot (in this case, a fatal or other serious crash)?

Do these teams have a "B" team in training to pull talent from, or possibly have a larger pilots roster that will rotate in and out throughout the season to pull from?  Maybe even have multiple teams that trade off show duties and training during the season?  

(I assume that the Thunderbirds will just paint up a new plane and give the pilot a good pep talk).
I can't answer for the Blue Angels or the Thunderbirds, but I can for the UK equivalent, the Red Arrows.

The Red Arrows have no spare pilots (or 'B team'). The nine pilots on the team fly every display in their 3 year tour. The explanation is that a spare pilot would not fly frequently enough to be current and safe. They do however have the capability to do an 8-plane display (rather than the usual 9) which they can use if a pilot is temporarily incapacitated. They also have a spare plane, something I know also applies to the Thunderbirds.

In the event of any kind of serious accident, it is likely that displays would be suspended for at least a while, in order to investigate and also out of respect. If all pilots are available when displays resume everything would be normal, using the spare plane if required. If a pilot was out for a short time they might fly the 8-plane display. The Arrows fly standard planes with minimal modifications, so presumably a new one could be readied fairly quickly.

In 2010 when Flt Lt. Ling was injured too badly to continue with display flying he was replaced by a pilot who had already flown with the team in a previous season.