I did a fresh install of the wallet and now I have like 4-5 months of transactions that are now listed as "generated but not accepted mined"
Will those transactions come back or did I lose all those coins trying to update the wallet?
it looks like you were on a fork, not the real LINDA chain. If you were on a version less than v2 (which was a hard fork, ie new blocks are not compatible with old ones), then those coins are invalid, whether you had updated your wallet or not. Had you tried to send them anywhere your transaction would have failed.
Now we are on v3 (which is also a hard fork, but a poorly publicized one), and anyone still on v2 will likewise be on a fork and will lose any coins generated after block 585200