We expect Microsoft to officially announce the LTE version of the Surface Pro 2017 at their 'Future Decoded' in London. However, an online retailer has just listed two Intel i5 based variants for pre-order with pricing details and shipping expectations.
https://www.notebookcheck.net/Online-retailer-starts-pre-orders-for-the-Surface-Pro-2017-LTE-edition-before-it-is-officially-annouced.249652.0.html
I was ready to buy the non LTE model soon. so I guess I'll just wait for this one, day one for sure!
If you're needing to buy soon, just keep in mind that the LTE model isn't expected until near the end of the year.