Any chance that's the case for that 1c?
Great question Billsey!
It had never occurred to me, but makes a lot of sense,
I did question myself, the CDS that appeared unusual,
but had no solution.
I do not recall reading any literature on Postal / Revenue / Telegraph use,
needs some research.
Telegraph strikes, 3 with normal "Telegraph and Star" cancellations
3 with CDS (Circular Date stamps)
2 with IQUIQUE
similar hammers !