RPM's for Buffet Lines?

Please forgive me for cross posting this (it's in catering also) but I'm feeling a little desperate, event is tommorrow, we live in a rural area so locating equipment, etc. is a major effort.

How fast do people travel through a buffet line? Is there a factor or a rule of thumb? Or, How many people per hour can be served in a continous line with a 4 item app/salad table moving on to a 6 item hot table?

A local restaurant family is having a wedding, our kids are friends since gradeschool, they family still has limited english. I offered to supervise the servers and buffet so they could enjoy the family event. 2 cooks from their restaurant (no english) will produce food, I'll take it from there. I've never done much buffet, and it has only been for 100+/-, in my own place. They don't do any volume this way either.
The rented facility has a great kitchen one salad buffet and hot table, we can get two lines though. I think we may need to set up another line.

I think expecting a person through each line every 1 minute is long, but I think 2 through the line a minute or every 30 seconds is optimistic. My gut feel is that for 350+ people, one 2 sided buffet is not enough, that another buffet is required, but to set up more than that is overkill.

Thought I should up date you, after the great response you gave me to my production question. The Chinese Wedding or what is also known as the very longest day of my life just consumed me, keep in mind I OFFERED TO PUT MYSELF IN THIS POSITION, I'D HELP CO-ORDIANTE THE RECEPTION EFFORT SO THE FAMILY COULD ENJOY THE EVENT ........... The first red flag should have been the wedding planner announcing she was a Seventh Day Adventist, and that she wouldn't actually be able to work the day of the wedding, which was on a Saturday............. Let this always be a warning to you..............leave immediately....even if required to jump out of multi-story high-rise building window, then it only hurt for a little while.............. Second, ignored warning...........the barely able to speak English, Filipino waitress from Chinese restaurant has arranged for the entire wait staff......3 more of some limited banquet experience, unknown Asian heritage, English not primary language................four more in the range of 14 or 15 yrs old, only experience is holding game joystick in hand.........language experience is English "huh" as only a teenager can grunt it, while exhibiting a blank look of non-comprehension on face...................Third, warning......2 midget Chinese cooks, requiring a step stool to reach stove top...... only speaking Chinese..... and of course,only understanding Chinese.............. I was on a dead run from 7 am till mid night. I borrowed equipment from every restaurant close by as hall had nothing, family had understood everything was furnished ..........wedding planner did not think to include food area in floral/decorative effort.........had to raid Easter/xmas decorations/grocery store flowers........... had to get a fish Tote of ice (4'by4'by4' box) from local seafood processor........ must have ice for four hundred people......no alcohol at this event except for champagne toast........ whiskey stash in back of pick-up became very important, a high priority by nine o'clock.......... my Asian bilingual daughter-in law of Filipino heritage kept breaking up the staff's attempts to rebel and organize a union against me.... that was a full time effort....................no one had a name like Sam, Jane, Sally......... all had names like So-slo-me.......Me-hida-noworke........ I resorted to saying "Tall one, both hands"..............or my favorite......."You, short one! Two pitchers! Carry two pitchers!............ We sat up three buffet lines, got everyone fed in less than an hour. .............. Half of staff disappeared at clean-up...............wedding planner didn't schedule any one to clean hall..........she thought "guests would just volunteer to help out"......... no, I don't know what planet she's from...... She has left a long detailed message on my cell phone, saying how great it was to work with me, and how she will highly recommend me to all of her wedding clients.............I've decided that it's best that I don't respond...........in a few days, I'll be able to express myself in a more calm, concise manner........ with out the spitting, gestures and four letter words. On the bright side, I can now mime "more eggrolls" and "more wonton" in a foreign language, and so it can easily been seen at knee level.

It only took two pain pills and a half of bottle of crown for me to lay down and sleep.