Susie, I'd say it's a new growth.
Like most sympodial orchids, bulbophyllums bloom only once from a mature pseudobulb. However, it's only the newest, fully developed pseudobulbs that will generally bloom (that's the front one on each "string" of pseudobulbs). In this case that's the one that's just started to put out a new crop of roots in the last picture. If that one hasn't flowered yet, then there's a good chance it will flower later this year. Pseudobulbs that have flowered previously won't flower again and even those that for whatever reason didn't bloom after they matured, won't bloom if they have a newer pseudobulb growing ahead of them (this only applies to those species that produce one new pseudobulb at the tip of each lead per year, those that produce several pseudobulbs in succession in one year can have all of the new pseudobulbs bloom at the same time).
Those thick nobs at the base of the older pseudobulbs are meristems. All pseudobulbs have them and some of them naturally develop into new growths to help the plant branch, particularly if the leading pseudobulb is damaged and the plant can't continue growing from it. So there's a chance that later this year or early next year, you will have 2 pseudobulbs with flower spikes (the one at the lead that is producing roots right now and the one that's just started growing and is producing a new branch from the oldest pseudobulb).