You must use a TSU at GH to have breakfast downstairs. Anyway, the quality has declined somewhat over the years and I honestly think having breakfast at the Grand Club is almost on par as having it downstairs - you don't get barista coffees but much nicer views and atmosphere in return. They can also make a la carte off menu dishes if you wanted.

Re the new subway station - it is of limited use (perhaps the most appreciated bit would be direct access to Shenzhen) - you will likely be better off cabbing to Central/Admiralty or walking to Wanchai station, unless with a lot of luggage. The walk to the new station from GH is also much more convoluted than walking to the station from the Ren.

Anyway, I doubt the HR TST had any renovations as the owner has been cutting corners over the years as well. Probably just very well maintenance (which is expected for HK).