No. The terminology is confusing to some. "Solid" bullet has always meant "non-expanding", and still does. It has nothing to do with "homogenous". There are jacketed solids and homogenous solids, as well as jacketed and homogenous expanding bullets.

The "nickel based bullet" referred to was their terminology for the metal-based lead bullet used mostly in the Nitro for Black loadings. The "solid nickel bullet" was the ubiquitous full nickel jacket, round nose - a purely conventional lead core FMJ with a nickel jacket - that was loaded in double rifle ammunition from the the appearance of the Nitros in the 1890s until the early 1950s, at which time the jacket was changed to gilding metal. The British sporting FMJ of that day was always referred to as "solid nickel bullet", and the jacketed soft point as "soft nose nickel bullet". You'll find reference to both engraved on the barrels of a great many British sporting rifles.

In the large double rifle Nitro Expresses, the ordinary nickel jacket RN "solid" worked well, and there was little demand to improve it. However, some of the new high velocity magazine rifles produced enough failures with them that Kynoch introduced nickel covered steel jacket solids - and softs - for a few of them shortly after WWI, but these weren't offered in the large DR rounds, as they weren't needed in those. After WWII, due to cost and, probably, supply (war rationing was still in force), it was found impractical to continue to use nickel for the jacket material, and plain gilding metal was used instead. These solids failed miserably, and Kynoch began offering gilding metal covered steel jacketed RN solids in double rifle ammunition in 1950-51.

The British never made an homogenous sporting bullet.