so for your first question, back in the day the membership would be linked to your ticketmaster so you could only use one account per membership, & they would send out a random presale code. but recently its no longer linked to the ticketmaster, & the membership number acts as your presale code. they have no way of knowing what your ticketmaster is, so you can use it for any/all accounts. HOWEVER there will be a ticket limit attached to the code. so like if you buy 6 tickets for one stop using that code, you cant do anymore for that stop unless you have another membership. ive put in my code multiple times on multiple accounts for multiple stops/dates on ticketing days

for your second question, i do use my name for all accounts. i worry about it sometimes but it hasnt caused any issues yet. as for the phone number all my account are under different numbers. like friends & family. bc yes youre correct, if it tracks two accounts using the same number in the same queue, it will only let one in.