So when the dual-colored check lands like Botanical Sanctum from Kaladesh rotate out, can we expect a new set of comparable lands for all color combinations? Or does the availability of these lands change from time to time?

I've read that GRN will feature 5 guilds and its expansion will cover the remaining 5. Is that an indication either way?

The dual lands in standard change with sets - there was a point in the past when we had tri-lands, for example. So no: you cannot expect a new set of comparable lands. For UG for example, you could get cycling lands, fast lands (like Botanical Sanctum), checklands (Hinterland Harbor), manlands (Lumbering Falls), etc. Not every two colors might have duals, too.

I see thanks. When do they usually publish new cards? Looks like there will be a major meta shakedown

The next block takes place in a multicolor settings, so you can probably expect some powerful dual lands. I suspect we;ll see a mix of enemy and ally color duals with each set in the block, based on the guilds featured.

The lands generally come ad go with the expansions. There was a Standard format not long ago when fetchlands and battle-lands were legal at the same time (Bloodstained Mire and Sunken Hollow, for instance), which obviously allowed for ridiculously good manabases.

So far, we only know Evolving Wilds and checklands (Rootbound Crag, for example) as legal lands in the post-October standard. However, knowing the next block is Ravnica, there is a good chance they'll reprint the shocklands for the five guilds featured in the set (Temple Garden, for instance), which would replace the Cycling lands (Irrigated Farmland) as checkland enablers.