Really back in the package holiday heydays it was the Tour Operators who saw & called the demand as more and more regional airports were being added from the 1960's onwards and LBA certainly saw decent IT holiday work mainly using BKS Viscounts, and mainly to Majorca.
I cannot say when the first jet flights started at LBA but I think these were flown in first by Spanish based airlines.
Thomson holidays by the mid 1970's were gaining a huge foothold from almost every UK airport and the 737 was the ultimate machine in terms of size and the better performance that came along after offered more destinations over the 'norm' of Majorca.
I think they Thomsons, using BY flew from over 20 UK airports.
The NE region's original main Tour Operator was Airways Holidays and BKS was their biggest customer with flights on their Britannias and Tridents from NCL and MME.
LBA and MME could also fill a holiday flight season, even though the nearby airports of NCL & MAN saw most of the IT traffic.
Of course back then it was always Majorca and also the Costa Brava that were the main destinations flown from UK Regionals.
Holiday Companies recognised that regional holidays could sell, and we would see many smaller local ones spring up to offer regular departures from the likes of the then tiny SEN & STN selling alongside LTN and LGW.
BRS, CWL, NCL, BHX and even CDD also had a good choice of departures.
All destinations were seasonal; most holidays were sold then as 2 weekers, and the charter flights season was quite short, flown mainly at weekends.
There was no or not much winter flying then from the smaller regionals.
That would open up in later years.
At the beginning Tour Operators tended to concentrate their main departures from either where they, or where their in-house airline was based.
To example a snapshot of the early few majors =
LTN
Skytours/Thomsons/Riviera = Britannia
Clarksons = Autair/Court Line
Cosmos = Monarch
Lunn Poly/Everyman = Dan Air (new 1-11 base began 1969 after British Eagle went bust at LHR)
CWL/BRS
Hourmont Travel = Cambrian (Cambrian had an IT series from LPL base)
SEN/STN
Mediterranean Holidays
Lyons Tours } = Channel Airways
BHX/CDD
Jetway/Mato/Ellerman/Horizon Midlands = BMA
MAN/LPL
Arrowsmith Holidays = Laker and Cambrian
Global = Caledonian and Cambrian
LGW
Horizon and Wings = BUA
Global = Caledonian
Lord Bros = Laker
Enterprise/Flair/Hickie Borman/Martin Rooks/Sovereign = BEA Airtours
Thomas Cook = BEA Airtours
NCL/LBA/MME
Airways Holidays = BKS
Obviously many Tour Operators also used Dan Air, plus the likes of Spantax Aviaco Air Spain and Transeuropa Etc...
Clarksons used Dan Air for their LGW and MAN programmes, and their Comets from LTN for longer flights.
Court Line flew the BHX, NCL, GLA, CWL, and BRS departures for Clarksons.
This was way before the likes of Intasun or Horizon started up their own in-house airlines much later in 1979.
Yugotours was one operator in particular that flew from almost every UK airport to Pula, Dubrovnik and Split.
Balkan Holidays was another one who flew to Bulgaria's beaches through Varna & Bourgas from many UK regionals.
Both using its own countries charter airlines.
One chap Fred Pontin started building his own holiday club resort hotels for his new venture Pontinental - the first in 1964 at Cala Mesquida Majorca, then more holiday villages sprang up in Spain, Majorca, Sardinia, Ibiza, Greece, Morocco and Yugoslavia.
The Hotel Pontinental in Torremolinos was built by Pontins in 1970 and five years later it was expanded by building a second similar hotel next door.
The buildings were known as Pontinental I and II.
He offered his own flights from all over the UK using OU, BY, KT, MON, BR, DA, AO/IB and BX filling dozens of flights each week. (Didn't do LBA though)