Here the 1874 RLDS edition replaced the conjunctive and with now as the narrative connector. The RLDS text has retained the use of now, even though the and is in 𝓟. Either reading is, of course, possible. The occurrence of and as the narrative connector before “it came to pass” is by far the most frequent one, but there are also many occurrences of “now it came to pass” (as well as “and now it came to pass”). In each instance, the critical text will follow the earliest reading, thus “and it came to pass” here in Alma 47:18.
Summary: Maintain in Alma 47:18 the original conjunction and before “it came to pass”, the reading of all the earliest textual sources (including 𝓞).