Leroy, I had something similar 15 yes ago, a discetomy but lower down L5/6. at the time I would swim up to 18 ams a week and recover for it was swimming for everyone else except for me. The neuro reckoned I would over do it and stuff up the procedure by loading up the back. I was restricted to walking....boring.
He was pretty right too, I went back a little early and was getting back pain, so pulled my head in, every time I saw him or the PHYSIO was can I swim yet. I had to wait 3 months, killed me it was over summer

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But it was worth the wait, went back to swimming for another 10 yrs, missing the water got me into SUP!!!
Good luck with it, I remember the pain and they say childbirth is bad.......it's got nothing on chronic back pain
Greg