What the everyday cup is
A description of something people do now, compiled from published accounts rather than from practice.
A bag of strong blended black tea — usually Assam-led with African CTC — in a mug, brewed two to three minutes, with milk and often sugar. 'Builder's tea' names the strong end of it. The tea is chosen for consistency and strength through milk rather than for origin character, and CTC manufacture exists substantially to serve this.
Making tea as a social act
A description of something people do now, compiled from published accounts rather than from practice.
Offering to make tea is a recognised gesture with meaning beyond the drink: it marks arrival, condolence, negotiation and repair. Workplace round-buying has its own informal rules. Anyone describing British tea drinking purely as a beverage preference has missed most of what it does.
The milk-first argument
A description of something people do now, compiled from published accounts rather than from practice.
Whether milk goes in before or after the tea has been argued about for a long time. The practical case for milk first is that it avoids scalding the milk with very hot tea; the case for tea first is that it lets strength be judged. With teabags in mugs the question is largely moot, which has not reduced the enthusiasm for it.