[ladytron]

Now take that offer and plan on getting out of this company in the next 6 months. Look for a big multinational with a long term vision with interesting work. You can now go to conferences and network with your new title and pay level.

I think this current company is not great if they were willing to underpay and then reverse course quickly only when they thought there was a counteroffer. I think your job is likely to not go well and you should start looking AGAIN immediately at a higher quality company. While you still have employment.