Christmas / New Year Holiday for IB

I'm gunning for IBD recruiting and I'm aware of other WSO posts mentioning that it's inappropriate to have networking calls during the holidays. However, I'm unsure about the holiday timing for each bank. Saw some bankers said it's a 2 week rest and some says 1 week or even less. Can I know if the policy is generally the same from bank to bank or it differs by each firm (or even each group)? I don't want to look stupid and offensive sending emails to bankers during the holiday but I don't wanna waste the opportunity to network (when they're on their jobs) either.