You can still come on an L1. They are independent petitions.
When you filed your I-130, I'm assuming you indicated you would be doing consular processing?
Someone here can correct me if I'm wrong, but I don't believe you can do AOS unless you start over. Your current petition so based on marriage to a US citizen. If you were to come and attempt to adjust, it would have to be off of your work visa, so filing an I-140, waiting for it's approval, then filing the I-485, I-765, etc. It will take longer than a year. Many people are issued work authorization but still have a long road ahead before they receive an interview and then finally, the greencard. If you leave it as is, you'll have to go back to the UK for your interview, but you're a few months away from I-130 approval and then the London consulate doesn't take long for interviews. Hopefully you'd have your spousal based GC before your work term ended.
No reason a spousal green card should be negatively impacted by a work visa.