80% of my briskets have been frozen once purchased...same reason as yours...only I usually bought by the case back in the day. There will always be some purge of liquid during thawing, but there is also a lot of moisture evaporation during cooking...can't stop that from happening (well, I actually have used a method to try to reduce it), but the purge from thawing is a minimal amount in the grand scheme of things.
Go ahead and grab what you need when you can...thaw in the fridge, allowing approx 6hrs/lb for brisket in 38* fridge...7-8hrs/lb if your fridge is very cold, say 34*. Freezer temps and fridge temps effect thawing time. My meat freezer, at -20*, will create very long thaw times compared to the typical 0* freezer temps...about 40% longer. Same goes for the fridge...colder takes longer. Place it in a large pan or on a cookie sheet to catch drippings from punctured/cut bag, if possible, and do not place meats over fresh foods, especially if they will be eaten raw...you probably already know that. Check it daily, and gently turn it over (don't want to tear the package) so that if there are varied temps in your fridge the temp exposures on both sides will be averaged out to being the same...just something I do. The point muscle (thickest portion) may not be fully thawed, and may still have ice crystals, but can still be processed for cooking. Handling nearly thawed meat for 20-30 minutes on room temp surfaces with warm (soon to be cold hands) while trimming and applying dry rub is usually enough to finish the thaw.
I try to adhere to the sell by/use by date, so I like to mark the date when frozen with a sharpie and you can then quickly calculate how many days it can remain refrigerated after it has thawed, in case it thawed earlier than you planned for...just for piece of mind.
Eric
