I don't know where you get the 2.30 timing from.
One set of swabs was taken. They were submitted to the lab as DRH/33, rejected and the later resubmitted as DRH/44. The date of collection on the form for the resubmission was correct but the time had been recorded incorrectly, hence your 11am theory.
Time hand swabs were taken at 2.30pm is taken from a police document which states they were taken at that time...
Hand swabs should not have had their exhibit reference changed from DRH/33 to DRH/44, nor had its lab' item reference number altered from 17 to 75 - this suggests that some sort of deception has been pulled off. Furthermore, a bible had the exhibit references DRH/33 and DRH/44, so what the hell has been going on here? How can the hand swabs be DRH/33 and the bible be DRH/33? How can the hand swabs be DRH/44 and the bible be DRH/44?
So...
Seems like Essex police were disguising exhibits by giving them exhibit references which belonged to other exhibits? This is totally unacceptable, and very misleading because the police have clearly set out to try to pull the wool over everyone's eyes regarding the hand swabs and the bible...
Amidst all this confusion, DC Hammersley took the fingermarks of Sheila Caffell, but failed to give them an exhibit reference. If you do not give the fingerprint forms an exhibit reference it becomes impossible to trace and locate them, so that they can be examined for the presence of lead deposit mingled in with the ink and blood on the hands...