I have a flight that was booked via UA flying on LH F from DTW-FRA continuing on in LH J from FRA-MUC, then SA J from MUC-JNB. How many bags am I allowed on a mixed itinerary? My layover in FRA is over 10 hours. I hope to get out and check out the city for a bit. Will I get access to the First lounge on arrival? When I get back from checking out the town? Thank you!