Did the fabrication of pre-production or production a/c had to be stopped at some point to wait for in flight test results? Similar question: did the early flights revealed unforseen problems that needed to be sorted out before the program can move on?
Can't say I remember the production line being stopped to wait for flight results, but then the production rate wasn't that spectacular anyway and most of the changes (not all of them) came from wind tunnel and design developments.
All flight tests reveal unforeseen problems! This could result in a pause in the prototype/pre-production flight test programme whilst the test aircraft was being modified, but this didn't delay build of later vesrions.