The Rugby Football Union says it volition soon supply "clarity for the game" regarding the extremist caller tackle laws amid fears of a wide subordinate exodus.
The tackle tallness volition beryllium lowered to the waist from adjacent play for each levels isolated from the Premiership and Championship.
The RFU says "detailed guidelines" volition beryllium sent retired to players, coaches and referees.
"We recognize this is simply a important change," said a national spokesperson.
However, galore clubs, players, coaches, and officials person expressed their concerns to the BBC, brandishing the instrumentality alteration unworkable, lamenting a deficiency of consultation, and fearing a wide subordinate departure from the sport.
Manchester Rugby Club, successful the 5th tier of the English rugby pyramid, accidental they person "real concerns" the determination volition "kill playing numbers for adjacent year".
Sam Williams, skipper of Wasps FC, the amateur limb of erstwhile nonrecreational nine Wasps, said the absorption from his squad members had been "overwhelmingly negative, with astir suggesting it volition alteration their committedness to playing oregon marque them retire/change sports altogether".
Meanwhile a petition calling for the RFU to reverse its determination has amassed much than 30,000 signatures successful a small much than 24 hours.
"Dropping the tackle tallness to beneath the waist volition marque the crippled a farcical spectacle to watch," said the petition laminitis Ed Bartlett, a subordinate with Old Reigatian RFC successful the level-six Regional South East 2.
"I wholly recognize the request to marque the crippled safer and wherever imaginable destruct the head-on-head collisions, but no-one is forcing anyone to play rugby union."
There is besides interest astir the unit the instrumentality alteration volition enactment connected unpaid coaches and referees, with the caller tackle tallness coming into effect connected 1 July.
"The implementation of it leaves the grassroots crippled mode excessively small clip to adjust," said Dickon Moon, the long-standing manager of rugby astatine level-six London Cornish.
"How I americium meant to retrain our circa 100 players successful clip for the caller play erstwhile we lone bid erstwhile a week and person to besides usage pre-season to get players fit?"
The RFU says its determination has been taken aft six years of studies, and insists determination is beardown data-led grounds to amusement that lowering the tallness of the tackle reduces the hazard of 'head acceleration events'.
It has besides taken guidance from a palmy waist-high proceedings successful France, though that lone applied to the sixth tier and below.
The RFU has pledged to supply players, coaches and lucifer officials with a "multi-format programme of grooming and method support" to hole them for the caller laws.
An RFU spokesperson added: "We recognize this is simply a important alteration and the crippled volition person questions astir the item of the caller instrumentality variation, what it means for coaches and players and however the tackle volition beryllium refereed during antithetic phases of the game.
"Detailed instrumentality exertion guidelines and grooming materials volition beryllium provided implicit the coming weeks for players, coaches and lucifer officials to springiness clarity for the game.
"By making this determination now, the volition is to springiness the crippled clip to hole up of the caller season."
'Rugby is not an evasion sport'
While the alteration successful laws does not impact the nonrecreational crippled successful England, the plans person been criticised by immoderate of the game's biggest names.
"Rugby is not an 'evasion sport'," erstwhile New Zealand planetary Sonny Bill Williams wrote connected societal media.
"Rugby is astir creating abstraction done manipulating and moving defences, interaction is portion of the game."
Former Wales and Lions subordinate Mike Phillips added that players should expect "more reddish and yellowish cards" that would "spoil the game".
Harlequins' Joe Marler expressed his disapproval with a "mind-blown" emoji portion Gloucester's Lewis Ludlow said concussions would "go done the roof" successful the assemblage game.