5,376 (5,056) Cambridge Surprise Major

Donald F Morrison (no. 4613)
  2345678
  5738264
  8674523
  4263857
- 2357486
s 7386245
  6435728
s 5428673
s 8473562
s 3462857
  2547386
s 7586234
- 5634728
  4268573
  8723456
Repeat eleven times.

Alternate block:
  2345678
  5738264
- 7864523
- 8423756
- 4356872
  6732485
  2875643
- 8543267
  3657824
  7264385
  4825736
  5386472
  6732548
- 7248653
  8523764
- 5364872
- 3472586
  2846357
  6587234
 

Reduce to 5,056 by replacing any two consecutive parts by once instance of the alternate block.
Health warning for those with allergies: contains backstroke 87s.