it'd; probably; must(used, usually with another verb, to suggest a probability • They must be finding it very difficult to live in such a small house); apparently; I suppose so; shall be; must have(The miles appeared to be so long that the tourists sometimes thought they must have missed the road Johnny Bravo)
must(Модальный глагол must, кроме долженствования, может выражать предположение, граничащее с реальностью. В этих случаях он переводится как "должно быть" • That must be interesting. – Должно быть, это интересно. • He must have got the article he needed. – Он, должно быть, достал статью, которая ему нужна.Alex_Odeychuk)
was due to(+ infinitive • It was also thought more prudent for Mr Tillerson to travel to Moscow because he will get to meet President Vladimir Putin whereas Mr Johnson was only due to meet Mr Lavrov." (The Int'l Express) – должен был встретиться только сART Vancouver)