Sorry if this question is too broad. My professor (political science--history is not his specialty) said that while revolutions are often portrayed as the singular moments of change, feudal hierarchy and capitalist hierarchy sometimes existed in the same region and had small-scale conflicts. I think it was a vague passing comment to think of the change in power relations in more gradual terms, rather than looking for singular moments of change, but it got me wondering if there were any examples of such conflicts.
Actually the starting idea of that there was a transition from feudalism to capitalism in England has been overturned by post-WWII into economic history.
For example, the evidence is that wage labour and markets were widespread in England centuries before the industrial revolution. To quote from one source:
At least one-third of the population of late medieval England gained all or a part of their livelihood by earning wages.
(Source Simon A. C. Penn, & Dyer, C. (1990). Wages and Earnings in Late Medieval England: Evidence from the Enforcement of the Labour Laws. The Economic History Review, 43(3), new series, 356-376. doi:10.2307/2596938, https://www.jstor.org/stable/2596938?seq=1#metadata_info_tab_contents)
Production for markets also appears to have been widespread. To quote from a paper by the economic historian Gregory Clark: Markets and Economic Growth: The Grain Market of Medieval England:
Yet we will see below that as early as 1208 the English grain market was both extensive and efficient. The market was extensive in that transport and transactions costs were low enough that grain flowed freely throughout the economy from areas of plenty to those of scarcity. Thus the medieval agrarian economy offered plenty of scope for local specialization. The market was efficient in the sense that profit opportunities seem to have been largely exhausted. Grain was stored efficiently within the year. There was no feasting after the harvest followed by dearth in the later months of the year. Large amounts of grain was also stored between years in response to low prices to exploit profit opportunities from anticipated price increases. ... There is indeed little evidence of any institutional evolution in the grain market between 1208 and the Industrial Revolution.
That the agrarian economy could have been thoroughly organized by market forces at least 500 years before the Industrial Revolution is of some consequence for our thinking on the institutional prerequisites for modern economic growth.
(pages 1 - 2, Eventually published as Gregory Clark, 2015. "Markets before economic growth: the grain market of medieval England," Cliometrica, Journal of Historical Economics and Econometric History, Association Française de Cliométrie (AFC), vol. 9(3), pages 265-287, https://ideas.repec.org/a/afc/cliome/v9y2015i3p265-287.html )
Your professor is illustrating the downsides of specialism in academia.