Hi to everyone who replied with so much wonderful information to my query in April and I'm so sorry I didn't realise a full and complete debate had happened, which I could have engaged in! More than anything I want to say THANK YOU for seeing the reference to "near the Red Lion Inn" in the 1829 advert - a breakthrough advert which I also discovered for the first time after posting here. It is one of those times, after 25 years of research, I still have to admit missing the obvious! DUH... I now feel pretty sure I can identify the location on Soho Road or Street, or 'nearby' at least. For my friends involved in the Thomas Jackson project, this will be a glorious find.

To answer some of the points made... please see a one-page explainer here:
Thomas Jackson Explainer, Celia Renshaw (Aug 2026).docx, which includes a link to the Thomas Jackson Letters website and to an article I wrote about Thomas' rebellious father John Jackson. The 1821 advert by John Jackson from his ropery in Handsworth (presumably the same one as Thomas's) was another breakthrough find in newspapers.
In early September, I will be at Staffordshire History Centre trying to find more info about the family's ropemaking years there, and when they began. You are also right that in 1813 John Jackson, then of Ilkeston, advertised his new Flat Ropes in a Birmingham newspaper indicating an existing interest there, though he went through near-bankruptcy in Ilkeston in 1816, rescued by a local, wealthier non-conformist who bought him out. John Jackson's father was Charles Jackson, a chandler by trade. Chandlers often carried out ropemaking. Yesterday, I found a Charles Jackson in the 1798 Land Tax Redemption records for
Handsworth., occupying premises held by a 'Mr HAY'. The sum assessed was £6 3s, which is pretty substantial.
Jackson is a very common name of course - so is this total coincidence? Maybe, just maybe, Thomas' grandfather Charles began the shared ropemaking interest in Ilkeston and Handsworth (linked by canal?)
They also had another family ropemaking interest there, in Smethwick on Foundry Lane - the TURTONs held premises now occupied by Avery Weigh-Tronix - Thomas Jackson's first cousin Eli TURTON held that ropery in 1836 when he died (buried at Union Row Independent Chapel). Turtons are plentiful in the Staffs/Birmingham area.
Thank you to everyone once again for all the info and photos, which I will now, belatedly, add to my brain and my files. I'll report back when I've put all the pieces together.