No signs yet, but judging by the stage my own hives are at, we are still a long way from swarming. I re-organised a hive today, which had too much honey left over from the winter, and I noticed they had made a reasonable patch of drone cells ready on one foundationless comb, so they are at least thinking about drones; that seems to be a good indicator of a maturing colony. Our fruit trees and wild cherries etc. are only just coming into bloom, so we are way behind the south of England where swarms are being reported.
PS. I had some drawn frames from last season, stored outside inside two hive boxes. I had sealed them top and bottom to avoid pest infestation. But I reconsidered today and put them on a proper floor with the entrance set very narrow. There seems nothing to lose by leaving this as my sixth bait-hive. I'll be in and out of it every week, re-using the frames elsewhere, so I'll soon spot any problems.