My wife was able to successfully walk-in 20+ days early from her scheduled biometrics on her I-131. BUT we have been trying to expedite the I-131 for several months.
When we finally got the biometrics appointment scheduled (it took several tries across different channels), it was accompanied by a letter from USCIS stating that 1) they couldn't expedite the I-131 until biometrics were taken and 2) the biometrics appointment had been scheduled for 2/22/2021.
We also walked into our ASC at ~12pm and it was clearly not that busy. But I agree that it's worth a try if you live near your ASC and have some good documentation.
ValleyRocket got a reaction from Chancy in Walk-In Biometrics before appointment date. Experiences.