Hold time is proportionate to the thickest part of any given piece. Since overannealing is NOT an issue it's best to err on the side of caution with both the annealing temp and soak time.
968F is the accepted annealing temp for Effetre/Moretti, but again err on the side of caution and go with the highest temp you can without slumping or marring your work. Not all pyrometers/thermocouples are 100% accurate.
I have the formulae but they are extensive and boring so I'll summarize.
An example, A 1" thick piece of Effetre glass requires a calculated soak time of 76.2 minutes. 1/2" requires 38.1 minutes. For a bead you would measure from the hole to the surface eg. the radius of the bead to determine the thickest part.
Besides the soak temp and time the cooling rate from annealing temp to below the strain point which is just above 850F for Effetre/Moretti, is just as important. Again you can err on the side of caution and slow cool to below 600F for assurance.
About 200F degrees per hour is an acceptable cooling rate for a 1" thick effetre piece of effetre from annealing to below strain point.
With a 1/2" inch piece you can go about 800F degrees per hour to below strain point.
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