The house was built in 1956. All sinks, toilets, dishwasher and washing machine drain without issues. Had the septic pumped and repaired with new baffels.
One of the tubs is about 50 ft away from the other. The septic is just outside of one of the tubs which is about 10 ft from the outlet for the septic.
Would the tubs be on a separate drain?
Could both of the drum traps fail at the same time?
The tubs have been draining slowly for a couple of years... now they take a day to drain. I have augered the first few feet and came up with nothing significant.
What should be my next move?

You have drum traps? Then you can't snake from the tubs. I would open up the drum traps and snake from there. Here's a tip on opening up the cover.(see image) Good luck, Tom

If you can't access the drum trap by removing the cover then it may be time to replace them with new PVC drum traps... ;)